Method of fabricating C-clamp

ABSTRACT

The method of fabricating a C-clamp composed of a base section having a first jaw extending from one end thereof and a second jaw extending from the opposite end thereof to define a jaw opening. The free end of the first jaw is provided with a first clamp pad affixed thereto facing the jaw opening. An elongate pressure screw is threadedly mounted in the free end of the second jaw and is movable upon threaded rotation relative the second jaw towards and away from the first clamp pad. A polygonal head member having two parallel sides is formed at one end of the pressure screw. An elongate extruded handle having a channel-shaped cross section slidably receives the head member, the parallel sides of the head member being in sliding surface engagement with the inner walls of the handle member. The handle ends are formed to retain the handle on the head member. A swivel ball is formed at the opposite end of the pressure screw. A second clamp pad formed of an extruded member having an arcuate cross-section dimensionally corresponding to the swivel ball diameter, slidably receives the swivel ball. The sides of the extruder member are pinched on either side of the swivel ball to retain the ball between the pinched area in swiveling relation to the extruded member.

This is a divisional of application Ser. No. 675,978, filed Apr. 12,1976, now abandoned, which is the parent of continuation applicationSer. No. 797,070, filed May 16, 1977, entitled "C-CLAMP".

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention is in the field of C-clamps having spaced jaws defining ajaw opening, one of which threadedly supports a pressure screw forexerting clamping pressure against a clamped member positioned in thejaw opening.

2. Description of the Prior Art

C-clamps are well known as clamping members and generally are formed offorged ferrous materials having opposed spaced jaws, one of whichthreadably carries a pressure screw. The pressure screw ordinarily hasformed at one end thereof a transverse member which may be a cylindricalrod slidable in a transverse cylindrical aperture in the end of thescrew. At the opposite end of the screw, a clamping pad is mounted inswivel relationship to a ball joint on the screw end. The screw handleand swivel joint required special machining and consequently wereaccordingly expensive to manufacture.

SUMMARY OF THE INVENTION

A C-frame cut from a channel shaped extruded aluminum member has a basesection supporting at each end thereof first and second jaws to define ajaw opening. The first jaw supports at its free end a first clamp pad,which is serrated to provide a gripping surface. The free end of thesecond jaw threadedly supports a pressure screw having at one endthereof a conventional hexagonal bolt head and at the other end thereofa swivel ball member. An elongate extruded channel shaped member havingparallel inner walls dimensionally corresponding to the spacing betweenopposite parallel sides of the hexagonal bolt head, and having inwardlyformed lips, slidably receives the bolt head, with sliding surfacecontact being between the parallel head sides and the inner walls of theelongate member. The inwardly formed lips are in sliding engagement withthe underside of the bolt head to maintain transverse alignment of theextruded member with the pressure screw. The handle may be pinched ateach end for retention on the bolt head or may be crimped at each end toprovide retention and permit slidable positioning of the handle on thebolt head to obtain desired leverage and operation in close quarters.

A second extruded aluminum member having an arcuate cross sectioncorresponding to the diameter of the swivel ball, slidably receives theswivel ball. The ends of the second member are pinched inwardly toretain the member in swivel relationship with the ball. The outersurface of the second member forms a second clamping pad in facingrelationship with the first clamping pad. Alternatively, the secondclamping pad may be a heavy threaded washer threadedly engaged with theend of the clamping screw, making unnecessary the swivel ball. Thus aconventional threaded bolt may be used for the pressure screw furthereconomizing in the clamp construction.

The jaws may form obtuse angles with the base section in order toconserve material, lessen clamp dimension, and provide additional framestrength. A lug may be formed on the outer side of the first jaw tothreadedly receive an antenna stud to provide a removable mounting for avehicle mounted Citizen's Band (CB) antenna. Insulative washers areutilized in the stud mounting to electrically insulate the antenna fromthe lug. Alternatively, a hook-shaped member may be integrally formedwith the outer side of the first jaw to provide a hanging clamp hook. Asecond hook, formed integrally back-to-back with the first hook, may beformed on the outer side of the first jaw to provide a rope tie-downclamp.

It is therefore an object of this invention to provide a method offabricating a lightweight, sturdy, C-clamp that provides exceptionaleconomy of manufacture.

Another object of this invention is to provide in the method of theforegoing object, clamp components which may be made from readilyavailable parts and from extruded aluminum sections.

A still further object is to provide in the method of the foregoingobjects a clamp which may be economically manufactured for a multitudeof purposes.

The above-mentioned and other features and objects of this invention andthe manner of attaining them will become more apparent and the inventionitself will be best understood by reference to the following descriptionof an embodiment of the invention taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of a first embodiment of thisinvention;

FIG. 2 is an end view of the embodiment of FIG. 1;

FIG. 3 is a side elevational view of a second embodiment of thisinvention;

FIG. 4 is an end view of the embodiment of FIG. 3;

FIG. 5 is a side elevational view of a third embodiment of thisinvention;

FIG. 6 is an end view of the embodiment in FIG. 5;

FIG. 7 is an exploded, pre-assembled, view in perspective of a pressurescrew assembly;

FIG. 8 is an assembled view in perspective of the pressure screwassembly of FIG. 7;

FIG. 9 is an exploded pre-assembled view in perspective of a secondembodiment of a pressure screw assembly; and

FIG. 10 is a view in perspective of the embodiment of FIG. 9 assembled.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIGS. 1 and 2, a first preferred embodiment is shown havinga C-frame 20 with a base section 22, upper jaw 24 connected at the upperend thereof and lower jaw 26 connected at the lower end thereof. Frame20 is cut from an extruded section of 6063 heavy-tempered aluminumhaving a 75 Barco test for hardness. Frame strength may be controlled byvarying the width W of the cut section, the wider cut providing a higherstrength frame. The width W of frame 20 is shown in the end view of FIG.2. Section 22 has a planar surface 28 and parallel ribs 30 which providea supporting surface for standing frame 20 on base 22. Jaw 26 haspedestals 32 formed on the outer surface thereof to provide spacedsupports for standing frame 20 on jaw 26.

Jaws 24 and 26 define a jaw opening therebetween, with jaw 26 havingserrated clamp pad 34 affixed to the free end thereof, pad 34 facing thejaw opening. Jaw 26 forms a rounded arc 36 with base 22 which providesadded strength and minimizes corner cracking when clamping pressure isapplied between jaws 24 and 26. Similarly, jaw 24 forms a rounded arc 38with base section 22. Further, jaw 24 forms an obtuse angle with base 22to provide not only added strength but to conserve space while providinga large jaw opening.

Jaw 24 threadedly receives at its free end in threaded bore 40, pressurescrew 42 which has hexagonal head 44 formed at the upper end thereof andswivel ball 46 (FIGS. 7 and 8) formed at the lower end thereof. Elongatehandle 50 is cut from a channel-shaped extruded aluminum section havingbase 52 and sidewalls 54 and 56. The inner surfaces of walls 54 and 56are in close sliding contact with opposite parallel sides of hexagonalhead 44. Lips 58 and 60 are formed respectively on walls 54 and 56 andextend inwardly and upwardly against the underside of head 44 in slidingengagement therewith to stabilize handle 50 in a longitudinal direction.After head 44 is inserted in handle 50, each end of base 52 is depressedinwardly to form indentations 62 and 64 to prevent removal of handle 50from bolt head 44. However, handle 50 may be slid along head 44 toprovide increased leverage and also to operate pressure screw 42 inclose quarters. Turning of handle 50 will accordingly turn screw 42causing advancement or retraction relative jaw 24, depending ondirection of handle 50 rotation.

An extruded aluminum section 68 (FIGS. 7 and 8) has an arcuate groove 70with a diameter corresponding to the diameter of ball 46 so that thereis a close sliding fit therebetween. Ball 46 is inserted in groove 70and ends 72 and 74 are pinched to provide a swivel mounting for section68, the lower surface of which forms a second flat clamp pad 69 facingpad 34. Thus, a swivel pad is provided from an extruded section, addingfurther to the economy of manufacture of the C-clamp. In the clamp ofFIGS. 1 and 2, a portion of the clamping surface of pad 34 extendslaterally beyond pad 69 and the free end of jaw 24. Due to this featureof clamp construction, the clamp may be used in a number ofapplications, such as with truck caps, making unnecessary inserts forproviding a clamping grip.

Referring to FIGS. 3 and 4, an embodiment is shown which provides aremovable clamp for mounting citizen band (CB), rodtype antennas tovehicle doors and the like. Removing the antenna, guards against theftand with this embodiment, the antenna may be quickly and easily removedand safely stored in the vehicle when the operator leaves the vehicle.In this embodiment, a C-frame 80 has a base section 82, a first jaw 84extending from one end thereof and a second jaw 86 extending from theother end thereof to define a jaw opening therebetween. Ribs 88 areformed on the outer surface of section 82 to provide a standing supportfor the clamp on section 82. A pair of serrated surfaces 92 are formedon jaw 86 at approximately a 90° angle to one another and thus willaccept in clamped relation a cylindrical member such as a mirror postnormally mounted on a vehicle. A lug 94 is formed on and depends fromthe outer side of jaw 86 to removably receive with clearance antennastud 96 which is insertable through an opening 98 in lug 94. Stud 96 isinserted through electrical connector 102. Insulative washers 100 onstud 96 are on both sides of lug 94, the washers having annular flangeswhich fit into opening 98 to provide clearance between stud 96 andopening 98. Nut 104 threadedly secures stud 96 to lug 94. Thus, stud 96and nut 104 are electrically insulated from clamp 80. A threaded length103 is provided to threadedly receive an antenna holder, not shown.

Elongate pressure screw 106 is threadedly received in threaded bore 108of jaw 84. Screw 106 has a hexagonal head 110 at its upper end and aswivel ball 112 at its lower end. An elongate extruded handle 114 havingbase 116 and walls 118 and 120, receives head 110 in close slidingrelation with lips 122 and 124 which are formed inwardly and upwardlyfrom walls 118 and 120, respectively, in sliding relation to theunderside of head 110. After handle 114 is centered on head 110, thesidewalls 118 and 120 are pinched towards one another at ends 126 and128 to hold handle 114 in fixed, centered relation to head 110.

Clamp pad section 132 is constructed in a manner similar to section 68and assembled to ball 112 in a manner similar to the assembly of section68 to ball 46, to provide a swivel clamping pad.

Referring to FIGS. 5 and 6, the C-frame 130 has a base section 132connected at one end to jaw 134 and at the other end to jaw 136 whichdefine a jaw opening therebetween. As in the previous embodiments, frame130 may be cut from extruded aluminum. Serrated clamping pads 138 and140 are formed in laterally spaced relation of jaw 136 and face the jawopening. The spacing between pads 138 and 140 accepts and centersobjects with an arcuate or round surface and at the same time provides aplanar serrated surface for clamping flat surface objects. Twoback-to-back hooks 142 and 144 are integrally formed and depend from theunderside of jaw 136. Hooks 142 and 144 provide means for suspendingframe 130 and also provide an anchor for a rope tie.

Pressure screw 146 is threadedly received in threaded bore 148 in theend of jaw 134. Screw 146 is similar in construction to screw 42 in theembodiment of FIG. 1 and has hexagonal head 150 at one end thereof andswivel ball 152 at the other end thereof. Handle 154 is similar inconstruction to handle 50 in the embodiment of FIG. 1 and is assembledto head 150 in a similar manner that handle 50 is assembled to head 44.Thus handle 154 receives head 150 in a close sliding fit and hasdepressed indentations 156 and 158 at opposite handle ends to preventremoval of handle 154 from head 153. However, handle 154 is slidablebetween the indentations 156 and 158 to provide additional leverage andpressure screw operation in close quarters.

Referring to FIGS. 9 and 10, a pressure screw construction is shownwherein a standard hex-head bolt 160 may be used. Hexagonal head 162 isreceived in a close sliding fit in handle 164 which is similar inconstruction to handle 50. An indentation 166 is placed in end 168 ofhandle 164 to prevent removal of handle 164 from head 162 in onedirection. The opposite end 170 of handle 164 is uncrimped so that thehandle may be removed from that direction if desired. It is understoodthat the handles in any embodiment may be pinched as in FIGS. 4 and 5,or crimped as in FIGS. 1 and 2, depending on the application.

A heavy threaded washer 172 is threadedly received by the end of bolt160 after which the threads may be deformed by means of a metal punch toprevent removal of washer 172 from screw 160. In this manner a clampingpad is provided which rotates with the screw and is of minimum cost.

In the clamps of this invention, maximum use of extruded aluminum ismade. The clamp frames are made from extruded aluminum channels and thestrength of the frames may be varied by cutting the frames toappropriate width from the extruded channel. Further, the pressure screwhandles are cut from long lengths of extruded aluminum and receive thepressure screw heads in a close sliding fit to again provide alight-in-weight, strong, economical construction. The swivel clamp headis also made from extruded aluminum and has an inner arcuate diametercorresponding to the diameter of the swivel at the end of the screw andis pinched on either side to capture the swivel ball within the arcuategroove. The material used in all of the aforementioned aluminumextrusions preferably is 6063 heavy-tempered aluminum that has a 75Barco test for hardness.

While the head of the pressure screw shown in hexagonal (polygonal),other head shapes may be used, such as square, having flat sidesengageable with the handle sides 54 and 56 to prevent relative rotation;the term "Polygonal" as used in the claims is intended to include suchalternative shapes.

While there have been described above the principles of this inventionin connection with specific apparatus, it is to be clearly understoodthat this description is made only by way of example and not as alimitation to the scope of the invention.

I claim:
 1. The method of forming a handle comprising the steps of: p1transversely cutting sections from an extruded metallic channel-shapedmember;inserting a polygonal bolt head into a section; said bolt headhaving an interference fit with the sides of said section to preventrelative rotation thereof; and forming the section to a smallercross-sectional size than said head to prevent the withdrawal of thehead from the section.
 2. The method of claim 1 wherein said last stepcomprises pinching the sides of the channel-shaped section on eitherside of the head to retain the section on the head.
 3. The method ofclaim 1 wherein said last step comprises depressing an indentation insaid section on both sides of said head.
 4. The method of forming aswivel device for a C-clamp comprising the steps of forming a threadedmember with a swivel head and neck portion on one end thereof, said neckportion being of smaller dimension transversely of said member than saidhead,forming a metallic body with an open sided groove defined byinturned flanges, said groove and the open side thereof beingdimensioned to receive slidably said head and neck portion,respectively, said open side being narrower than said groove, insertingsaid swivel head into said groove with said neck portion being receivedbetween said flanges whereby said body is retained against dislodgmentfrom said swivel head longitudinally of said threaded member, anddeforming portions of said flanges on opposite sides of said swivel headinwardly to a transverse dimension that prevents withdrawal of said headfrom said groove longitudinally of the latter.
 5. The method of claim 4including the step of extruding a length of metal to the cross-sectionalshape of said body, and transversely cutting a section off said extrudedlength to provide said body.
 6. The method of claim 5 in which saidgroove in cross-section is of circular C-shape, said swivel head isspherical and said neck portion is circular, and said deforming stepincludes depressing said portions of said flanges into said groove tothereby reduce said groove opening on the opposite sides of said head toa size smaller than said neck portion.
 7. The method of claim 6 whereinsaid extrusion has a surface on the side opposite from the grooveopening which is essentially flat, said extrusion further being formedof aluminum.
 8. The method of fabricating a C-clamp comprising the stepsof cutting transverse sections from a first length of extruded metalwhich is essentially C-shaped in cross-section thereby to provide aplurality of clamping frames, threading a clamping bolt through one endportion of an arm of a frame such that the bolt may be threadedlyadjusted across the open side thereof to juxtaposition the bolt end withrespect to the other arm of said frame, providing a swivel head on saidbolt end defined by an enlarged portion spaced from the body of the boltby a reduced neck portion, cutting transverse sections from a secondlength of extruded metal having in cross-section a groove which isessentially C-shaped in cross-section thereby to provide a plurality ofclamping pads, assembling a pad onto said swivel head by inserting saidhead into the groove thereof with the edges of the groove slidablyfitting said reduced portion, the spacing between said groove edgesbeing less than the maximum transverse dimension of said swivel headwhereby said pad is longitudinally retained on said swivel head, anddeforming the C-shaped groove at the opposite ends of said pad to a sizesmaller than the transverse dimension of said neck portion thereby toretain said pad on said head, the fit between said pad and headproviding clearances that permit said pad to swivel on said head.
 9. Themethod of claim 8 in which said groove in cross-section is of circularC-shape, said swivel head is spherical and said neck portion iscircular, and said deforming step includes depressing said portions ofsaid flanges into said groove to thereby reduce said groove opening onthe opposite sides of said head to a size smaller than said neckportion.
 10. The method of claim 1 wherein said section is formed to anorthogonal shape with inturned flanges defining the open sidethereof,said bolt head having flats on opposite sides thereof whichslidably fit between the sides of said section, said bolt head having ashoulder on the underneath side thereof and further a thickness asprovides a sliding fit between said inturned flanges and the top of saidsection, said inserting step including slidably fitting said bolt headinto said channel section from one end thereof.